A temperature regulating apparatus for an air-circulated refrigerator is disclosed, capable of keeping the refrigeration room temperature constant by way of closely regulating the flow rate of cold air admitted into the refrigeration room. Also disclosed is a control device for controlling operation of the temperature regulating apparatus. Such a temperature regulating apparatus comprises a core member 50 either extendible to open up the cold air inlet port 12 or retractable to close off the same. A multiple turns of a coil 54 surrounds the core member 50 in order to produce a varying level of inductance i.e. an electrical signal proportional to the axial displacement of the core member 50. This electrical position signal is transmitted to a control device 20 which serves to control the operation of the damper flap actuator based on the temperature signal from a temperature sensor 22.